Is this implantation bleeding

Is this implantation bleeding

Hi I'm new to this site. For the last 3 cycles I have had mid cycle cramps and spotting. I had unprotected sex 2 days after my period ended and now a week later I have cramps back ache and brown spotting not enough to wear a pad and also had some strands of brown today. This is my third day of these symptoms.Is this ovulation or implantation as never had this before. Any advice would be greatly appreciated. Thx